SICKbot
This is a small ground vehicle I built as a platform for working on SLAM algorithms. It has a NAV200 LIDAR, a pan/tilt camera, WiFi, and tank drive with two DC motors. A Beagle Board for processing. An ATmega16 AVR microcontroller generates PWM signals for the DRV8801 motor drivers (the OMAP chip on the Beagle Board could do this, but I need other I/O as well, so it was easier to put everything in the ATmega).
The robot is powered by a 3000mAh 3S lithium-polymer battery pack. The AVR reports battery voltage to the OMAP so I don't deplete the pack.
The AVR communicates with the OMAP by SPI. The OMAP can also program the AVR over these lines, so no additional hardware or user intervention is required for programming.
I only recently assembled all the hardware, so currently there is no autonomy and some of the hardware features are not complete. The custom PCB has provisions for lights, a low-power 900MHz for remote power on/off, and a six degree of freedom IMU.